Re: Nvidia/X/console problem
I could narrow the problem down:
Using Runlevel 3, everything seems to work, until you leave X and try to restart X with startx again. This leads to a blank screen here (same behaviour as switching between console and X).
When you remove the unused nvidia module after leaving X with rmmod nvidia and do a startx again, the nvidia module is loaded automatically but everything works as expected again.
So, removing the module in between resolves the problem, but, of course you can only do this when you have left X already, not when just switching console and X via CTRL-ALT-F1/F7.
Maybe some experts have more ideas now?